from django.db import models
from django.contrib.auth.models import User

# Create your models here.
class Topic(models.Model):
	"""用户学习的主题"""
	text = models.CharField(max_length=200)
	date_added = models.DateTimeField(auto_now_add=True)
	owner = models.ForeignKey(User,on_delete=models.CASCADE)
	
	def __str__(self):
		"""返回模型的字符串表示"""
		return self.text

class Entry(models.Model):
	"""学到的有关某个主题的具体知识"""
	topic = models.ForeignKey(Topic,on_delete=models.CASCADE)
	text = models.TextField()
	date_added = models.DateTimeField(auto_now_add=True)
	
	class Meta:
		verbose_name_plural = 'entries'
		#当managed = False 的时候不会进行数据迁移操作，如果忘记了就生成不了表了，把它置为True
		managed = True
	
	def __str__(self):
		"""返回模型的字符串表示"""
		
		return self.text[:50] + "..."
